Yet another small RCT of probiotics. This time 150 infants less than 1500 grams birth weight in an NICU in Mexico were randomized to a mixture of 4 different Lactobacilli and Bifidobacterium infantis or control. There was a reduction in NEC stage 2 or greater (6/75 vs 12/75) of about the same magnitude as all the other trials. They also had lower mortality, and no adverse effects.

Here is the funnel plot with the new new study added. I can only say it again, its time we stopped doing placebo controlled RCTs and focused on finding the best preparation, and the optimal dose and timing. RCTs in women at risk of preterm delivery are also a good idea.

I am not aware of any current evidence that antenatal probiotics improve clinical outcomes in the preterm. There is one small RCT showing effects on Toll Like receptor expression in the placenta of mothers randomized to probiotics compared to controls (Rautava S, Collado MC, Salminen S, Isolauri E: Probiotics modulate host-microbe interaction in the placenta and fetal gut: A randomized, double-blind, placebo-controlled trial. Neonatology 2012, 102(3):178-184.) and this study also showed that they were able to find DNA from the organisms in some of the placentas and amniotic fluid. A couple of other studies have shown differing effects on bowel colonization of the newborn, born at term. I don’t know of studies that have given probiotics along with the antenatal steroids, for example.